NEW YORK — A catastrophic flood emptied New Orleans of much of its black youth. Powerful social forces may be doing a similar thing to places like Harlem and Chicago's South Side.
Over the past decade, the inner-city neighborhoods that have served for generations as citadels of African-American life and culture have been steadily draining of black children.
Last year's census found that the number of black, non-Hispanic children living in New York City had fallen by 22.4 percent in 10 years. In raw numbers, that meant 127,058 fewer black kids living in the city of Jay Z and Spike Lee, even as the number of black adults grew slightly.
The same pattern has repeated from coast to coast. Los Angeles saw a 31.8 percent decline in its population of black children, far surpassing the 6.9 percent drop in black adults. The number of black children in Atlanta fell by 27 percent. It was down 31 percent in Chicago and 37.6 percent in Detroit. Oakland, Calif. saw a drop of 42.3 percent.
Overall, the census found nearly a half-million fewer black children living in the 25 largest U.S. cities than there were a decade earlier. By comparison, the number of black adults living in big cities has hardly budged.
Demographics experts said a combination of factors appeared to be at work. Americans in general are having fewer children than they once did, due mostly to increased use of birth control. That has been true, too, among black mothers. Teen pregnancy rates among blacks have also plummeted.
But the more significant trend, experts said, may be a migration by young black parents to the suburbs.
For many, that pull of a place with safer streets, higher-achieving schools and more housing space for the dollar has apparently simply overridden any desire to stay in flawed inner-city neighborhoods, simply because they are black capitals.
"I'd been in Harlem for 16 years, and when I first came, I was young, and I was excited and it was a mecca. But progressively each year, it got rougher and rougher to be here," said Rachel Noerdlinger, a publicist whose clients include the Rev. Al Sharpton. "The violence. The profiling by the cops. I just started to get really, really frustrated."
Finally, she decamped across the Hudson River to the suburban quietude of Edgewater, N.J., taking her 14-year-old son with her.
New York state assemblyman Keith Wright, whose district covers central Harlem, has noticed fewer children in the area as well, but he, too, thinks the phenomenon has less to do with flight from crime or decay, and more to do with the high price of city living.
"A lot of our younger folks, I find, are moving to New Jersey. They think the city life is too expensive. It comes down to a matter of economics," Wright said.
Some black city residents, he said, are also migrating "back down South, where they think the dollar will go farther."
That migration has been evident in places like Henry County, Ga., an area of suburban Atlanta that has seen its black population more than triple in the past decade. Blacks now make up 37 percent of the county of nearly 204,000 people.
The trend has also been showing up in a less visible way in countless mostly white suburbs like Livonia, Mich., outside of Detroit. Just a decade ago, there were 951 black people living in the entire city, out of a population of around 100,000. Now there are 3,309. The same trend has repeated in white suburbs across the country.
"Face it: In a lot of suburbs, there was a distinct effort to keep blacks out," said David Bositis, a senior researcher at the Joint Center for Political and Economic Studies in Washington and a former Census Bureau demographer.
Those barriers have now been falling, he said, opening the door for blacks to follow in the footsteps of white families who had their own migration to the suburbs after World War II.